gdb/i386aix-nat.c

   1 /* Intel 386 native support.
   2    Copyright (C) 1988, 1989, 1991, 1992 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include "defs.h"
  22 #include "frame.h"
  23 #include "inferior.h"
  24 #include "language.h"
  25 #include "gdbcore.h"
  26
  27 #ifdef USG
  28 #include <sys/types.h>
  29 #endif
  30
  31 #include <sys/param.h>
  32 #include <sys/dir.h>
  33 #include <signal.h>
  34 #include <sys/user.h>
  35 #include <sys/ioctl.h>
  36 #include <fcntl.h>
  37
  38 #include <sys/file.h>
  39 #include "gdb_stat.h"
  40
  41 #include <stddef.h>
  42 #include <sys/ptrace.h>
  43
  44 /* Does AIX define this in <errno.h>?  */
  45 extern int errno;
  46
  47 #ifdef HAVE_SYS_REG_H
  48 #include <sys/reg.h>
  49 #endif
  50
  51 #include "floatformat.h"
  52
  53 #include "target.h"
  54
  55 static void fetch_core_registers (char *, unsigned, int, CORE_ADDR);
  56 \f
  57
  58 /* this table must line up with REGISTER_NAMES in tm-i386v.h */
  59 /* symbols like 'EAX' come from <sys/reg.h> */
  60 static int regmap[] =
  61 {
  62   EAX, ECX, EDX, EBX,
  63   USP, EBP, ESI, EDI,
  64   EIP, EFL, CS, SS,
  65   DS, ES, FS, GS,
  66 };
  67
  68 /* blockend is the value of u.u_ar0, and points to the
  69  * place where GS is stored
  70  */
  71
  72 int
  73 i386_register_u_addr (int blockend, int regnum)
  74 {
  75 #if 0
  76   /* this will be needed if fp registers are reinstated */
  77   /* for now, you can look at them with 'info float'
  78    * sys5 wont let you change them with ptrace anyway
  79    */
  80   if (regnum >= FP0_REGNUM && regnum <= FP7_REGNUM)
  81     {
  82       int ubase, fpstate;
  83       struct user u;
  84       ubase = blockend + 4 * (SS + 1) - KSTKSZ;
  85       fpstate = ubase + ((char *) &u.u_fpstate - (char *) &u);
  86       return (fpstate + 0x1c + 10 * (regnum - FP0_REGNUM));
  87     }
  88   else
  89 #endif
  90     return (blockend + 4 * regmap[regnum]);
  91
  92 }
  93
  94 /* The code below only work on the aix ps/2 (i386-ibm-aix) -
  95  * mtranle@paris - Sat Apr 11 10:34:12 1992
  96  */
  97
  98 struct env387
  99 {
 100   unsigned short control;
 101   unsigned short r0;
 102   unsigned short status;
 103   unsigned short r1;
 104   unsigned short tag;
 105   unsigned short r2;
 106   unsigned long eip;
 107   unsigned short code_seg;
 108   unsigned short opcode;
 109   unsigned long operand;
 110   unsigned short operand_seg;
 111   unsigned short r3;
 112   unsigned char regs[8][10];
 113 };
 114
 115 static
 116 print_387_status (unsigned short status, struct env387 *ep)
 117 {
 118   int i;
 119   int bothstatus;
 120   int top;
 121   int fpreg;
 122   unsigned char *p;
 123
 124   bothstatus = ((status != 0) && (ep->status != 0));
 125   if (status != 0)
 126     {
 127       if (bothstatus)
 128         printf_unfiltered ("u: ");
 129       print_387_status_word (status);
 130     }
 131
 132   if (ep->status != 0)
 133     {
 134       if (bothstatus)
 135         printf_unfiltered ("e: ");
 136       print_387_status_word (ep->status);
 137     }
 138
 139   print_387_control_word (ep->control);
 140   printf_unfiltered ("last exception: ");
 141   printf_unfiltered ("opcode %s; ", local_hex_string (ep->opcode));
 142   printf_unfiltered ("pc %s:", local_hex_string (ep->code_seg));
 143   printf_unfiltered ("%s; ", local_hex_string (ep->eip));
 144   printf_unfiltered ("operand %s", local_hex_string (ep->operand_seg));
 145   printf_unfiltered (":%s\n", local_hex_string (ep->operand));
 146
 147   top = ((ep->status >> 11) & 7);
 148
 149   printf_unfiltered ("regno  tag  msb              lsb  value\n");
 150   for (fpreg = 7; fpreg >= 0; fpreg--)
 151     {
 152       double val;
 153
 154       printf_unfiltered ("%s %d: ", fpreg == top ? "=>" : "  ", fpreg);
 155
 156       switch ((ep->tag >> ((7 - fpreg) * 2)) & 3)
 157         {
 158         case 0:
 159           printf_unfiltered ("valid ");
 160           break;
 161         case 1:
 162           printf_unfiltered ("zero  ");
 163           break;
 164         case 2:
 165           printf_unfiltered ("trap  ");
 166           break;
 167         case 3:
 168           printf_unfiltered ("empty ");
 169           break;
 170         }
 171       for (i = 9; i >= 0; i--)
 172         printf_unfiltered ("%02x", ep->regs[fpreg][i]);
 173
 174       i387_to_double ((char *) ep->regs[fpreg], (char *) &val);
 175       printf_unfiltered ("  %#g\n", val);
 176     }
 177 }
 178
 179 static struct env387 core_env387;
 180
 181 void
 182 i386_float_info (void)
 183 {
 184   struct env387 fps;
 185   int fpsaved = 0;
 186   /* We need to reverse the order of the registers.  Apparently AIX stores
 187      the highest-numbered ones first.  */
 188   struct env387 fps_fixed;
 189   int i;
 190
 191   if (inferior_pid)
 192     {
 193       char buf[10];
 194       unsigned short status;
 195
 196       ptrace (PT_READ_FPR, inferior_pid, buf, offsetof (struct env387, status));
 197       memcpy (&status, buf, sizeof (status));
 198       fpsaved = status;
 199     }
 200   else
 201     {
 202       if ((fpsaved = core_env387.status) != 0)
 203         memcpy (&fps, &core_env387, sizeof (fps));
 204     }
 205
 206   if (fpsaved == 0)
 207     {
 208       printf_unfiltered ("no floating point status saved\n");
 209       return;
 210     }
 211
 212   if (inferior_pid)
 213     {
 214       int offset;
 215       for (offset = 0; offset < sizeof (fps); offset += 10)
 216         {
 217           char buf[10];
 218           ptrace (PT_READ_FPR, inferior_pid, buf, offset);
 219           memcpy ((char *) &fps.control + offset, buf,
 220                   MIN (10, sizeof (fps) - offset));
 221         }
 222     }
 223   fps_fixed = fps;
 224   for (i = 0; i < 8; ++i)
 225     memcpy (fps_fixed.regs[i], fps.regs[7 - i], 10);
 226   print_387_status (0, &fps_fixed);
 227 }
 228
 229 /* Fetch one register.  */
 230 static void
 231 fetch_register (int regno)
 232 {
 233   char buf[MAX_REGISTER_RAW_SIZE];
 234   if (regno < FP0_REGNUM)
 235     *(int *) buf = ptrace (PT_READ_GPR, inferior_pid,
 236                            PT_REG (regmap[regno]), 0, 0);
 237   else
 238     ptrace (PT_READ_FPR, inferior_pid, buf,
 239             (regno - FP0_REGNUM) * 10 + offsetof (struct env387, regs));
 240   supply_register (regno, buf);
 241 }
 242
 243 void
 244 fetch_inferior_registers (int regno)
 245 {
 246   if (regno < 0)
 247     for (regno = 0; regno < NUM_REGS; regno++)
 248       fetch_register (regno);
 249   else
 250     fetch_register (regno);
 251 }
 252
 253 /* store one register */
 254 static void
 255 store_register (int regno)
 256 {
 257   char buf[80];
 258   errno = 0;
 259   if (regno < FP0_REGNUM)
 260     ptrace (PT_WRITE_GPR, inferior_pid, PT_REG (regmap[regno]),
 261             *(int *) &registers[REGISTER_BYTE (regno)], 0);
 262   else
 263     ptrace (PT_WRITE_FPR, inferior_pid, &registers[REGISTER_BYTE (regno)],
 264             (regno - FP0_REGNUM) * 10 + offsetof (struct env387, regs));
 265
 266   if (errno != 0)
 267     {
 268       sprintf (buf, "writing register number %d", regno);
 269       perror_with_name (buf);
 270     }
 271 }
 272
 273 /* Store our register values back into the inferior.
 274    If REGNO is -1, do this for all registers.
 275    Otherwise, REGNO specifies which register (so we can save time).  */
 276 void
 277 store_inferior_registers (int regno)
 278 {
 279   if (regno < 0)
 280     for (regno = 0; regno < NUM_REGS; regno++)
 281       store_register (regno);
 282   else
 283     store_register (regno);
 284 }
 285
 286 #ifndef CD_AX                   /* defined in sys/i386/coredump.h */
 287 #define CD_AX   0
 288 #define CD_BX   1
 289 #define CD_CX   2
 290 #define CD_DX   3
 291 #define CD_SI   4
 292 #define CD_DI   5
 293 #define CD_BP   6
 294 #define CD_SP   7
 295 #define CD_FL   8
 296 #define CD_IP   9
 297 #define CD_CS   10
 298 #define CD_DS   11
 299 #define CD_ES   12
 300 #define CD_FS   13
 301 #define CD_GS   14
 302 #define CD_SS   15
 303 #endif
 304
 305 /*
 306  * The order here in core_regmap[] has to be the same as in
 307  * regmap[] above.
 308  */
 309 static int core_regmap[] =
 310 {
 311   CD_AX, CD_CX, CD_DX, CD_BX,
 312   CD_SP, CD_BP, CD_SI, CD_DI,
 313   CD_IP, CD_FL, CD_CS, CD_SS,
 314   CD_DS, CD_ES, CD_FS, CD_GS,
 315 };
 316
 317 /* Provide registers to GDB from a core file.
 318
 319    CORE_REG_SECT points to an array of bytes, which were obtained from
 320    a core file which BFD thinks might contain register contents.
 321    CORE_REG_SIZE is its size.
 322
 323    WHICH says which register set corelow suspects this is:
 324      0 --- the general-purpose register set
 325      2 --- the floating-point register set
 326
 327    REG_ADDR isn't used.  */
 328
 329 static void
 330 fetch_core_registers (char *core_reg_sect, unsigned core_reg_size,
 331                       int which, CORE_ADDR reg_addr)
 332 {
 333
 334   if (which == 0)
 335     {
 336       /* Integer registers */
 337
 338 #define cd_regs(n) ((int *)core_reg_sect)[n]
 339 #define regs(n) *((int *) &registers[REGISTER_BYTE (n)])
 340
 341       int i;
 342       for (i = 0; i < FP0_REGNUM; i++)
 343         regs (i) = cd_regs (core_regmap[i]);
 344     }
 345   else if (which == 2)
 346     {
 347       /* Floating point registers */
 348
 349       if (core_reg_size >= sizeof (core_env387))
 350         memcpy (&core_env387, core_reg_sect, core_reg_size);
 351       else
 352         fprintf_unfiltered (gdb_stderr, "Couldn't read float regs from core file\n");
 353     }
 354 }
 355 \f
 356
 357 /* Register that we are able to handle i386aix core file formats.
 358    FIXME: is this really bfd_target_unknown_flavour? */
 359
 360 static struct core_fns i386aix_core_fns =
 361 {
 362   bfd_target_unknown_flavour,           /* core_flavour */
 363   default_check_format,                 /* check_format */
 364   default_core_sniffer,                 /* core_sniffer */
 365   fetch_core_registers,                 /* core_read_registers */
 366   NULL                                  /* next */
 367 };
 368
 369 void
 370 _initialize_core_i386aix (void)
 371 {
 372   add_core_fns (&i386aix_core_fns);
 373 }